The present invention relates to an improved earphone for use with communication equipment emitting radio frequency (RF) radiation, such as cellular telephones or others, in which hazardous risks are reduced.
In recent years there has been an explosion in the extent of use of cellular telephones. Particularly popular are such telephones, which are small, hand held devices comprising a mouthpiece and an ear piece and including within it the entire communication circuitry. A major problem which has been identified in recent years, associated with the use of such device, is the RF radiation emitted thereby, which is believed to cause an accumulating hazardous effect, particularly on brain tissue, which is proximal to the RF-emitting antenna.
The RF radiation can in principle be shielded by various means, but these are heavy, cumbersome and thus not user friendly. Another drawback of such shielding arrangements is that they can interfere with the quality of reception and transmission.
The intensity of the radiation diminishes as a square function of the distance from the source of radiation, i.e. from the antenna. Accordingly, devices have been suggested which may be attached to the ear piece to increase distance between the antenna and the user""s head. In order not to affect the hearing ability of the sound emitted from the ear piece, it has also been suggested to use a spacer with walls defining a sound channel for sound transmission from the ear piece to the user""s ear. An example of such a device is that described in German Utility Model DE 97-U2-00243.
Other devices which provide a permanent sound channel between the ear piece and the user""s ear, i.e. not having collapsible walls, are also known, such as that described in U.S. Pat. No. 5,564,085.
It has recently become common to use personal ear pieces detachably connectable to the cellular telephones which are equipped with an integral microphone fitted on the cord connecting the ear piece to the cellular phone. Such ear pieces provide improved acoustics and isolation from surrounding noise and for a while it has been believed that the significantly increased distance of the antenna of a cellular phone from the user""s head eliminates the hazardous affect of radiation. However, some recent researchers have shown to the contrary, namely that the ear piece plugged into the user""s ear emits radiation at rates which are significantly higher than those transmitted from the antenna and which are extremely hazardous.
It is thus an object of the present invention to provide an improved ear piece in order to reduce or eliminate the radiation from the user""s head. Iot is a specific object of the invention to provide an earphone which can be attached to an ear piece of such a communication device to form a sound channel between the ear piece and the users ear.
The invention is concerned with an acoustic earphone for retaining an earphone connected to a radio transmitting device at an extended distance from the user""s head whereby acoustic communication is facilitated via an acoustic tube.
In accordance with the present invention there is provided an acoustic earphone for transmitting sound from a transducer sound source, the earphone comprising a sound transmitting tube portion extending between an ear tip member for engaging the external ear canal of a user, and a sound receiving end fitted to said sound source.
According to one embodiment of the invention, the sound receiving end is integrally formed or fixedly attached to the sound source. According to another embodiment, the sound receiving end is removably attached to the sound source which, by a typical example of the invention is an earphone connected via a wire to the mobile cellular phone.
By still another embodiment of the invention, either one or both of the sound source, namely earphone, and the sound receiving end is fitted with a Faraday cage providing an electrostatic shield, preventing or reducing radiation from the earphone.
Preferably, at an operative state, the sound transmitting tube defines a minimal distance between the earphone and the user""s ear of at least about 3 cm
By another aspect of the present invention, the earphone is adapted for placing adjacent a user""s ear and where the housing thereof is received win a Faraday cage, typically made of a mesh wire, for reducing or eliminating radiation of a magnetic wave.